192 possible plain sandwiches can be made because you would do 4x6x8 which equals 192.
7tens8ones
6tens18ones
5tens28ones
4tens38ones
3tens48ones
2tens58ones
1tens68ones
0tens78<span>ones</span>
The first one because if you add all the positives you get 4 and then if you add all the negatives you get 7 so then you do 4+(-7)= -3